Dental casting-machine.



1. E. BURNS.

DENTAL CASTING MACHl NE APPLICATION FILED NOV. 24, 191

Patented J My 16, 1918.

y 2 U 2 mm J N N\ m- 4 I 9, am M Y A TTOH/VEV I ll DVLEAFEE% PATENT JQHN E. BURNS, 0E FLUSHING, NEW YORK.

DENTAL CASTINGJwIACHINE Specification of Letters Fatcnt. Patented July R6, @918.

Application filed November 24, 1917. Serial No. 293,685.

To all whom it may concern:

Be it known that 1, JO N E. Burns, a citizen of the United States, and resident of Flushing, in the county of Queens and State of New York, have invented. certain new and useful improvements in Dental Casting- Machines, of which the following is a specification. L

This invention relates to dental casting machines and more especially to means for closing the molding flask with a cap through which compressed air is then admitted to the flask and upon the molten metal, the object of the invention being to automatically admit the air as the cap closes the flask and by the continued movement of the operating" lever, as will be more fully described in the following specification, set forth in the appended claims and illustrated in the accompanying drawings, wherein:

Figure 1 is a side elevation of the improved. casting machine partly in section.

Fig. 2 is a Vertical sectional view through the cap plunger. I

Fig. 3 is a fragmentary view showlng the cap and plunger depressed.

Fig. a is a front elevation partly in section.

l-Vhere dental casting machines are used in which themolten metal is subjected to it is very necessary that the air be admitted automatically so that one of the hands of the operator shall remain free to attend to other matters. ln order to easily and quickly produce this result sisting of the base 5 and upright 6, the lat ter having the overhanging member with anopening 8 through which plays a plunger 9 having a cap 10 at its lower end and directly above the flask 11. that is supported. on a platform 12 of the base 5.

The flask 11 may be of any desired type to contain the mold while the cap 10 may be provided with the necessary packing to make an air tight fit so that the colnpresse air will not escape, and the upper end of the plunger 9 carries a valve casing 13 with an inlet pipe 1% at one side and an outlet pipe 15 at the other the action of compressed air.

side and the latter is flexible and communicates with the interior oi? the cap 10. The connnnnication between the inlet and the outlet is interrupted by the valve 16, as will be seen in Fig. 2, carried at the upper end of a rod or stem 17 whose lower end is screwed into the hub 18 of the cap lug 20 on the member a machine is provided con l0. Theweight of the cap seats the valve and the compressed air from the pipe la 18 normally shut oil. Acertain amount of play is allowed the end of the plunger in the hub 18 so that the rod 17 and the valve ma move independently. i

he plunger is operated by alever 19 pivoted to a link 20 that is loosely 7 while a goose neck 21 extends upward and forms a guide for the plunger. The angular extension 22 of the lever 19 is" pivoted to the collar 23 that encircles and is secured to the plunger and limits its upward and downward movement. VJhen the plunger is depressed into the bolted to a p position shown in Fig. 3 the movement of I the recess of the hub 18 and causes the valve seat 25 to drop away from the valve so that the compressed air passes through the easing 13 and the outlet pipe 15. On reaching the cap the inr-ushing air is diffused by the inclined nipple 26 to prevent injury to'the molten metal and its being blown from the mold.

It is obvious that while the parts shown and described are simple and readil operable they may be modified and 0t erwise arranged without departing from the essential features above scope. of the appended claims.

What I claim as new is:

1. In a dental casting machine, the combination of a flask, a cap to close the same, a source of compressed air for the cap, a valve controlling the same, a plunger loosely playing on and adapted to depress the cap and carrying the valve, means for operat= ing the plunger, and a stem below the valve and attached to and adapted to be operated by the cap to open the valve when it is seated on the flash.

2. In a dental casting machine, the com bination of a flask for a mold, a cap with a nipple to close the same, a compressed air pipe connected to the nipple, a plunger with ahead constituting a part of the air pipe, a valve closing the air pipe, a stem to the valve and secured to the cap, means for providing lost motion between the plunger and the cap, and means for depressing the plunger.

described or from the adapted to close the same, a plunger above the cap, means for operating the plunger, a valve casing at the top of the plunger and having an air outlet, an outlet pipe connecting the casing with the interior of the cap,

a valve between the inlet and outlet, a valve lower end and playing through the upright,

a valve casing at the top of the plunger, air supply means passing through the casing to the cap, an interposed valve, a stem for the same passing down the plunger and attached to the,cap. means for affording movement of the eap on the plunger, and a lever operating the plunge 5. In a dental casting machine, the combination with a flask, of an upright With an overhang, a plunger playing through thelatter, a cap playing on the end of the plunger, a valve casing atthe top of the plunger and having an inlet, an outlet pipe for the air and connected with the interior of the cap, a valve interposed between the inlet and outlet, astem for the valve and suspending the cap, and a lever operatlngthe plunger.

Signed at 354 Livingston street, in the county of Kings and State of New York, this 21st day of November, A. D. 1917. i

JOHN E. BURNS. 

